The User Datagram Protocol (UDP) is simplest Transport Layer communication
protocol available of the TCP/IP protocol suite. It involves minimum amount of
communication mechanism. UDP is said to be an unreliable transport protocol but it
uses IP services which provides best effort delivery mechanism.
In UDP, the receiver does not generate an acknowledgement of packet received and
in turn, the sender does not wait for any acknowledgement of packet sent. This
shortcoming makes this protocol unreliable as well as easier on processing.
Requirement of UDP
A question may arise, why do we need an unreliable protocol to transport the data?
We deploy UDP where the acknowledgement packets share significant amount of
bandwidth along with the actual data. For example, in case of video streaming,
thousands of packets are forwarded towards its users. Acknowledging all the packets
is troublesome and may contain huge amount of bandwidth wastage. The best
delivery mechanism of underlying IP protocol ensures best efforts to deliver its
packets, but even if some packets in video streaming get lost, the impact is not
calamitous and can be ignored easily. Loss of few packets in video and voice traffic
sometimes goes unnoticed.
Features
UDP is used when acknowledgement of data does not hold any significance.
UDP is good protocol for data flowing in one direction.
UDP is simple and suitable for query based communications.
UDP is not connection oriented.
UDP does not provide congestion control mechanism.
UDP does not guarantee ordered delivery of data.
UDP is stateless.
UDP is suitable protocol for streaming applications such as VoIP, multimedia
streaming.
UDP Header
UDP header is as simple as its function.
24. USER DATAGRAM PROTOCOL
